1. Field of the Invention
The present invention relates to a fan cover having a fan motor for cooling electronic parts. The present invention also relates to a motor drive unit including the fan cover.
2. Description of the Related Art
A motor drive unit is provided with a fan motor for cooling electronic parts arranged inside a drive unit. FIG. 8A is a perspective front view of a fan cover of the prior art. FIG. 8B is a perspective rear view of the fan cover of the prior art. As shown in FIG. 8A, the fan cover 100 has an opening portion 120 in which air passes from a fan motor (not shown in FIG. 8A). As shown in FIG. 8B, two protruding portions 130 for supporting the fan motor are arranged around the opening portion 120.
FIG. 8C is a side view of the fan cover of the prior art. As shown in FIG. 8C, the fan motor 110 is supported by two protruding portions 130 so that the fan motor 110 can face the opening portion 120.
Specifically, as shown in FIG. 8D, which is a partially enlarged view of FIG. 8C, the fan motor 110 is engaged with the supporting portion 140 located at an end portion of the protruding portion 130.
When the fan motor 110 is driven it vibrates, which is transmitted between the fan motor 110 and the fan cover 100. Further, the vibration is transmitted between the fan cover 100 and the main body case (not shown) for holding the fan cover 100. As a result, noise is generated and the reliability of parts of the motor drive unit may be deteriorated.
Therefore, according to the official gazette of JP-A-5168188, a vibration isolating rubber is arranged between the fan motor and the main body case so as to suppress the vibration of the fan motor.
However, in the case of the official gazette of JP-A-5168188, it is necessary to prepare the vibration isolating rubber. Accordingly, a number of parts increases and the production cost of the motor drive unit is raised. Further, since the vibration isolating rubber deteriorates with age, it takes time and labor to maintain the motor drive unit.
The present invention has been accomplished in view of the above circumstances. An object of the present invention is to provide a fan cover capable of suppressing vibration of the fan motor without using vibration isolating rubber and also provide a motor drive unit including such a fan cover.